Ultra-sensitive detection of pathogenic microorganism using surface-engineered impedimetric immunosensor
Ultra-sensitive detection of pathogenic microorganism using surface-engineered impedimetric immunosensor
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DOI：
10.1016/j.snb.2011.11.041
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发表时间：
2012-01-03
影响因子：
8.4
通讯作者：
Kim, Young-Rok
中科院分区：
文献类型：
--
作者：
Joung, Cho-Kyung;Kim, Han-Nah;Kim, Young-Rok
描述了一种用于高灵敏度和特异性致病菌检测的无标记电化学免疫传感器。为了提高电化学阻抗谱（EIS）免疫传感器的灵敏度，在金电极表面修饰了一层具有生物相容性和亲水性的透明质酸（HA），通过抗e，极大地提高了模型微生物大肠杆菌0157:H7的捕获效率。大肠杆菌0157:H7抗体结合到HA层。为了定量检测，在氧化还原探针[Fe(CN)(6)]（3-/4-）存在下，通过归一化阻抗变化（NIC）分析0.1 Hz时阻抗的大小随目标细菌浓度的变化。0.1 Hz时阻抗大小随目标菌浓度（10-10(5)cfu/mL）线性增加，检出限极低（类似于7cfu/mL）。这是迄今为止最灵敏的非pcr细菌检测传感器之一。该系统对非目标细菌，如金黄色葡萄球菌、蜡样芽孢杆菌和非致病性大肠杆菌DH5 α的反应即使在高浓度下也可以忽略不计，这证实了抗体- ha修饰的免疫传感器的高度特异性。(C) 2011 Elsevier B.V.版权所有
A label-free electrochemical immunosensor for highly sensitive and specific detection of pathogenic bacteria is described. To increase the sensitivity of electrochemical impedance spectroscopy (EIS) based immunosensor the surface of gold electrode was engineered with a biocompatible and hydrophilic layer of hyaluronic acid (HA) which greatly enhanced the capture efficiency of model microorganisms, Escherichia coli 0157:H7 through anti-E. coli 0157:H7 antibody conjugated onto the HA layer. For quantitative detection, the magnitude of impedance at 0.1 Hz in the presence of redox probe, [Fe(CN)(6)](3-/4-), was analyzed by normalized impedance change (NIC) with respect to varying concentration of target bacteria. The magnitude of impedance at 0.1 Hz increased linearly with the concentration of target bacteria (10-10(5) cfu/mL) with an extremely low limit of detection (similar to 7cfu/mL). This is by far one of the most sensitive non-PCR based sensors for bacterial detection. The responses of this system against non-target bacteria, Staphylococcus aureus, Bacillus cereus and non-pathogenic E. coli DH5 alpha were negligible even at a high concentration, which confirms the highly specific nature of antibody-HA modified immunosensor. (C) 2011 Elsevier B.V. All rights reserved.